Archive for month: November, 2018

The Link Between Soil and CO2

Did you know that according to the US governments analysis of grassland ecosystems in the year 2000, only 3% of the tall grass prairie that was once in North America is still intact?This loss has had a huge impact on the way our entire ecosystem works, but what is little known is the massive loss of soil carbon that has accompanied the loss of prairie land.All of that carbon from the soil has been released into the atmosphere and is responsible for about one third of the increase in atmospheric CO2 over the last 150 years.Turning Earth, LLC says more carbon has gone into the atmosphere from the soil than from fossil fuel between 1860 and 1970.

Soil carbon and its impact on climate change is the subject of intensifying scientific research, and with good reason.The findings of current research are expanding our knowledge of how soil sequesters carbon and how our own effort to regenerate the soil with compost can slow down the rapid rise of CO2 in the atmosphere.

Overall, the world’s soil holds about three times as much carbon as the atmosphere and recognition of its capacity to take up atmospheric CO2 is catalyzing a significant shift in the direction of the battle against global warming.The focus thus far has been in quelling emissions from the burning of fossil fuels; however crucial that reduction may be, scientists now find that soil carbon sequestration, known as a carbon “sink”, is as a promising a weapon in the fight and one that can be utilized by everyone from large agricultural and governmental organizations to individual home owners.

According to Rattan Lal, Director of Ohio State University’s Carbon Management and Sequestration Center, the world’s soils have lost between 50% and 70% of their original carbon stock, much of which oxidized when exposed to air, becoming CO2 when the soil was cultivated. Places like the North American prairie, the North China Plan and even the arid interior of Australia are now being considered future carbon sinks based on the rapidly expanding knowledge of carbon sequestration in soils.Researchers are studying how land restoration projects in these areas might bring back carbon, nitrogen and, thereby, the natural fertility these areas have lost.“We cannot feed people if soil is degraded,” Lal says.

When soil is tilled or disturbed in any way the carbon in it is exposed to the air, an oxygen source.The carbon atoms attach to the oxygen forming CO2 a potent greenhouse gas.Conventional farming practices continuously remove plant material that has grown each season that, in the natural system, would return to the soil when the plant dies.In countries like India farmers literally burn the dead plant material off the fields in order to clear the land for the next planting. Besides putting harmful smoke into the air, these intensive farming practices remove further carbon from the soil adding to the deterioration that has been rampant throughout the world for decades.

Regenerative agricultural practices like no till farming, planting of “green manure” cover crops, and top dressing the field with compost can turn back the carbon clock, reducing atmospheric CO2 while raising soil fertility and decreasing vulnerability to floods and drought.

Plants pull carbon out of the air through photosynthesis forming carbon compounds that are the structure of the plant body itself or biomass.What the plant doesn’t need for growth is secreted through the roots and becomes food for soil organisms like microbes and fungi.This is known as the humification of carbon, a process in which the carbon is made stable in the soil. Humus, whose main component is carbon, gives soil the ability to hold water, determines its structure, and gives it fertility.

Lal estimates the potential to store carbon in the top layer of degraded and desertified soils around the world could amount to 1 – 3 billion tons of carbon annually, equal to approximately 3.5 to 11 billion tons of CO2 emissions. Active soil carbon which is located in the topsoil (generally the top 15 to 30 centimeters) is continually exchanging carbon between microbes living in the soil and the atmosphere. Bolstering soil microbiology by adding compost restores normal soil activity in places where it has been interrupted by the use of insecticides, herbicides, or fertilizers.

It is currently unknown how much carbon is stored in deep carbon pools well below the active layer of soil, it is thought that soil below the five meter depth may store carbon at much higher rates than shallower soils. Encouraging finding are coming in from scientists studying some deep rooted grasses in Australia with below-ground plant structures that plunge more than five meters deep sequestering carbon all the way down.

The Marin Carbon Project

The Marin Carbon Project was started in 2007 when local farmers concerned about the impact of global climate change on the productivity of their farms.Located in the San Francisco Bay Area the group now includes farmers, researchers, government agencies, and nonprofits who are working to enhance soil carbon sequestration in farm land, range land, and forests.The aim is to improve farm productivity and the health of the local ecosystem while mitigating climate change. Citing research that showed dairy farms had more carbon in their soils than the adjacent grasslands because farmers sprayed manure on fields as a way of recycling the waste.This group believed that they could improve soil quality and offset CO2 emissions produced by agriculture by putting compost on grasslands.

Lead by researcher Whendee Silver of the University of California at Berkley, the Marin Carbon Project showed that applying composted agricultural and green waste to grasslands sequesters carbon at a rate of 1 metric ton per year.The fields that the project treated with compost also had higher forage production due to higher fertility and better ability to hold water in the soil.The conclusion after nine years of steady results is that applying organic matter to soils is one of the most effective ways currently available to divert CO2 from the atmosphere.

According to the Food and Agriculture Organization of the United Nations, grasslands comprise 40.5% of the earth’s terrestrial area excluding Greenland and Antarctica.The use of chemicals that kill soil microbes and fungi, overgrazing, erosion, fires and simple poor land management have robbed of much of this land of its carbon and carbon-storing ability.

Expanding the practices of the Marin Project to just 25% of California’s grasslands, Silver projects that the carbon sequestration rate would be 21 million metric tons of carbon per year. Grasslands, farm lands and uninhabited lands, with the addition of compost, could return carbon to the soil, reduce greenhouse gas emissions and divert green waste from landfills.

Organics Diversion and Methane Avoidance

Besides the large scale application of compost to grasslands, small scale composting not only sequesters carbon but prevents the production of methane in landfills. Organic “green” waste in the conventional waste stream decomposes in anaerobic (without oxygen) conditions producing methane which, according to the Environmental Defense Fund, is 84x more potent as a green house gas than CO2 in the first 20 years after its release into the atmosphere because of its ability to absorb heat from the sun.

In its Basic Information About Landfil Gas, the EPA states that municipal solid waste landfills are the third-largest source of human-related methane emissions in the United States, accounting for approximately 14.1% of these emissions in 2016. Composting organic waste such as food scraps, grass clippings and paper, allows the organic materials to decompose aerobically which prevents the production of methane. The US sent 31 million tons of food waste to landfills in 2007, composting this waste would have been the equivalent of taking 8.4 million cars off the road.

Residential and commercial lawns and gardens are essentially the same as an agricultural field with low biodiversity, soil depletion and lack of soil organic carbon especially if chemical fertilizers, pesticides and herbicides are in use. Every homeowner can impact global warming by converting their land to organic maintenance practices and by composting all biodegradable household waste and applying it to the landscape.

“Fighting global warming is not out of our reach, it’s as close as our own back yard.”

More and more research around the world has shown the inestimable importance of sequestering carbon into the soil by composting and reducing methane emissions by keeping organic materials out of the landfill. On December 1st Raleigh area residents and church leaders will gather to learn about how they as individuals and community members can make a real difference in the fight to slow or even reverse climate change.

All attendees will be treated with a sumptuous lunch provided by Green Planet Catering, a locally owned and operated business that is unique not only to the Triangle area but the entire country. With a focus on Triple-bottom-line business tactics, Green Planet Catering has made a decision to lead the catering market in developing a business model that is devoted to creating sustainable solutions.

Drew is dedicated to spreading the message of San Francisco’s Zero Waste policies across the globe. As Senior Residential and Special Projects Zero Waste Coordinator at the San Francisco Department of the Environment, he oversees the Fantastic 3 residential collection program. With his oversight, the program diverts 100,000 tons of recyclables and 50,000 tons of organics every year. Drew’s expertise comes from over two decades of directing non-profit recycling and reuse operations and shaping resource conservation policy at local and statewide levels.

Drew works closely with SFE’s Environment Now (EN) team to bring a personal, culturally resonant explanation of programs, with a call to action on climate change and stewardship, to every San Francisco resident. He also manages the Zero Waste and Urban Sustainability grant program which has distributed up to $1,000,000 to non-profits annually.

and

Noel Lyons, McGill Environmental Systems

Noel Lyons co-founded McGill Environmental Systems with Jim McGill in 1991. The company just celebrated its 27th year in the composting industry with Noel celebrating his 18th year as company President.

Though McGill operates facilities in North Carolina, Virginia and Ireland, North Carolina is home for both the company and Noel, who resides in Cary. The company employs about 100 people and composts about 360,000 tons of biodegradable materials including yard waste, biosolids, and food waste annually. To date, McGill has composted over 5 million tons. McGill’s hundreds of customers include municipalities, Fortune 500 companies, garden centers, landscapers, agriculture and the sports turf industry.

Under Lyons’ leadership, McGill has built its business on convincing customers and regulators that composting can be a serious, environmentally and economically sustainable technology. This has been achieved to a great degree.

He sees as the next big challenge and opportunity the need to inform people of the potential for compost use to mitigate climate change by creating healthy soils that sequester carbon.

Noel’s resume includes more than 25 years of experience in every aspect of compost manufacturing and sales. He holds a degree in Agriculture Science from the Waterford Institute of Technology in Ireland and a certificate of Technical Competence in Composting from the University of Maine Cooperative Extension.

Did you know there is an official day to celebrate dirt? Well, there is and it’s December 5th.

We know that soil is the source of most of our food and is a finite natural resource; on a human time-scale it is non-renewable. Even with this knowledge, degradation of soil resources continue worldwide because of inappropriate management practices and pollution. So, in 2002, The International Union of Soil Sciences (IUSS), adopted a resolution proposing the 5th of December as World Soil Day to celebrate the importance of soil as a critical component of the natural system and as a vital contributor to human wellbeing.

Composting is the only way that we humans can conserve and restore soil health both globally and in our own backyards. So here at the NC Composting Council we are embracing the celebration of World Soil Day with a countdown of soil facts which began on November 1st and ends on December 4th. We offer you one question and one answer for each of the 34 days. Click the link below and learn more about soil. Then go out and COMPOST!!